Control structure for vending machine



June 8, 1965 R. T. CORNELIUS ETAL 3,188,160

CONTROL STRUCTURE FOR VENDING MACHINE Filed June 13, 1963 3 Sheets-Sheet 1 I 1/ I Illlllllll'fn VII/Il a I 1 June 1965 R. 1'. CORNELIUS ETAL 3,188,160

CQNTROL STRUCTURE FOR VENDING MACHINE Filed June 15, 1965 3 Sheets-Sheet 2 I'IINVENTORS BMWTCOIflQJQ" J 1965 R. T. CORNELIUS ETAL 3,188,160

CONTROL STRUCTURE FOR VENDING MACHINE 3 Sheets-Sheet 3 Filed June 13. 1963 INVENTORS 7 W051 United States Patent CONTROL STRUCTURE FOR VENDING MACHINE Richard T. Cornelius, Minneapolis, and Irving F. Snyder, Anoka, Minm, assignors to The Cornelius Company, Anoka,-Minn., a corporation of Minnesota Filed June 13, 1963, Ser. No. 287,696 19 Claims. (Cl. 312-220) This invention relates generally to vending machines, and more specifically to structure for a machine which in- .cludes a plurality of product doors which are suitably interconnected and controlled.

Although the principles of the present invention may be included in various vending machines, a particularly useful application is made in a vending machine of the type that is employed with bottled beverages. In particular, machines have been previously provided which employ a number of shelves or racks, each terminating at a discharge gate which is rendered movable in response to the previous deposit of a requisite size or number of coins. Ithas been customary to provide a single door in the cabinet at such gates, such door being freely openab'le at any time without the deposit of a coin. In such a machine, it is possible to decap a bottle while the bottle is in the machine, allowing the bottle contents to drain into a cup, or removing the bottle contents by a straw or a siphon.

In accordance with the principles of the present inven tion, there is a separate product door provided at each gate, the door being openable only in response to the deposit of the requisite coinage. Rather than employ one coin mechanism for each door, there is provided an interlock mechanism by which all of the doors are under the control of one coin mechanism, any single door being openable when the coin deposit has been made. Conversely, the interlock mechanism prevents the unauthorized or simultaneous opening of any second door when the first door has been opened. Of course, an appropriate antijack-potting mechanism is used in conjunction therewith, which is not illustrated herein and which does not form a part of the present invention.

An individual door of the type described could serve as an effective lever to damage the control mechanism in the absence of a coin deposit. Accordingly, additional means, other than the coin mechanism, are provided to prevent unauthorized door opening, and more particularly, to prevent forces derived from an attempt to open such door from being applied to any great extent to the coin mechanism.

Accordingly, it is an object of the present invention to provide an improved control structure for a vending machine.

Another object of the present invention is to provide an interlock structure for multiple product doors of an article vending machine.

Yet another object of the presentinvention is to provide means by which product access doors of a vending machine may not be simultaneously opened.

A still further object of the present invention is to provide means by which the coin mechanism is protected from forces originating with the attempted opening of one of the product doors when no coin deposit has been made.

Another object of the present invention is to provide a door interlock structure wherein no more than one slide member is provided per product door.

Many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.

On the drawings:

FIGURE 1 is a front elevational view of a fragmentary portion of a vending machine;

FIGURE 2 is a cross-sectional view taken along line 1-III of FIGURE '1;

FIGURE -3 is an elevational view taken, along line III-III of FIGURE 2;

FIGURE 4 is a fragmentary portion of FIGURE 3 illustrating the relationship of the parts when one door is open; and

FIGURE 5 is a fragmentary cross-sectional view of further control means associated with the mechanism shown in FIGURE 2.

As shown on the drawings:

The principles of this invention are particularly useful when embodied in a vending machine such as is fragmentarily illustrated in FIGURE 1, generally indicated by the numeral 110. The vending machine 10 includes internal structure (not shown) by which articles to be vended or dispensed are successively delivered to a number of vending stations, each one of which is closed by one ofa series or plurality of product doors 11, 12, and 13. The number of doors is to some extent optional depending upon the size and complexity desired to be built into the vending machine 10. A typical machine may employ as few as two such doors, but preferably includes a larger number such as a number from four to six doors. Each door is provided with a knob 14 by which the same may be grasped for opening.

One advantage of this structure is that the owner of the machine, such as a national bottling company, may provide indicia 15 on one or more of the doors, such as the door 12, indicating its product name or names. Not only will this provide the expected advertising of such product, but the presence of the name on the door will deter the unauthorized placement of other brands therein by one having access to the machine for refilling the same. Thus, this structure will tend to discourage the occasional practice or occurrence of finding armachine carrying a recognized brand name prominently displayed on the outside thereof, but finding only other brands on the inside, each of which is typically shown on the bottle cap of a bottle in such other machine. Since in the present structure the contents behind a particular door are not necessarily visible, it is more likely that the party filling the machine will provide the brand name indicated on the door.

Each of the plurality or series of doors 11- 13 etc., is pivotally supported for swinging about a common axis. In the illustration, the axis is shown as being vertical, but may equally well be horizontal. To this end, there is provided an elongated shaft 15 which is supported remotely from the doors 11-16 for being pivoted about its axis.

Each of the doors 1143 is aligned with an access opening 16 shown in FIGURE 2, and is swingable or pivotable from a normally closed position as shown in FIGURE 2 to an open position as shown in chain lines also in FIGURE 2. The door '12 is typical of the others and includes a cylindrical hub portion 17 through which the shaft 15 extends, there being a nylon bearing sleeve '18 disposed therebetween.

To each of the doors such as 12, and more particularly to each of the hub portions 17, there is fixedly and rigidly secured one element forming a part ofmeans for preventing simultaneous opening of any other door. To 'this end, such element comprises a control block 20 which may be Welded to or cast as an integral part of the remainder of the door 12. a

The control block 20 is best seen in FIGURE 3. As any one of the doors 11-13 is swung about its axis, the corresponding control block 20 is likewise pivoted about a the same axis. When all of the doors 11-13 are closed, the various control blocks 20 are aligned with each other as shown in FIGURE 3.

The upper portion of each control block 29 comprises a cam block or surface 21 which blends into a surface 22 lying in a plane perpendicular to the pivotal axis. The lower portion of each control block 20 comprises a stop means 23 having one surface 24 which lies substantially parallel to the pivotal axis and another surface 25 which is substantially perpendicular to the pivotal axis. In this embodiment, the cam block portion or surface 21 is integral with the stop means portion 23. The cam block portion or surface 21 may be omitted from the endmost one of the control blocks 20, and the stop means 23 may be omitted from the opposite endmost one of the control blocks 20.

There is provided a number of slide members as lying in a common plane and each slidably supported as by a .group of nylon guide blocks 27. Each slide member 26 .lies between a pair of control blocks 21).

Each slide member 26 is provided with a roller 28 which normally engages the cam surface 21 of one of the pair of control ,blocks 20 between which such slide member 25 lies.

Each slide member 26 is also provided with a notch 25 which is receptive of the stop means or lower portion of adjacent hub portions 17 by a spacer 31, such as of nylon. Preferably, each of the nylon spacers 31 is fixed to the shaft or to other stationary structure so that it cannot move axially. At least the endmost spacers 31 must be so fixed.

In order for any of the doors 11-13 to pivot, that is in order for any of the hub portions 17 thereof to pivot, the control block acting through its cam surface 21 must'engage and shift the adjacent slide member 26 to allow the roller 28 to ride up onto the surface 22 of such control block 20. If the lowermost control block 24) is pivoted, all of the slide members 26 are shifted since each slide member 26 abuts the next. If the uppermost illustrated slide member 26 is held stationary, then no control block 20 could move. Yet, the end surface of each control block 20 overlies the end of the adjacent slide member 26 when pivoted so that all of the slide members 26 atthat side thereof are prevented from moving. Each slide member 26 is movable by one of the control blocks or cam blocks 20 into blocking juxtaposition with the next adjacent control or cam block. By the coaction of the surfaces 24 and 29, pivoting of the associated product doors is precluded. Yet, each slide member 26 is held by the stop means 25 which is engageable with the end surface 32 in blocking juxtaposition with the next lower illustrated cam block 20 to prevent pivoting thereof.

As any one slide member 26 is shifted by one of the control blocks 20, such slide member 26 successively engages and moves any other slide members 26 at one side thereof so as to place the notches 29 in juxtaposition with the control blocks 21) at such side thereof. Further, as any such one control block 213 is pivoted, it holds any non-shifted slide member at the other side thereof in a non-shiftable position, such slide member successively engaging and holding any further slide members 26 in fixed position. Each slide member 26, considered by itself, is movable to two slide member positions in one of which it blocks one control block 20, and in the 4 other of which positions it blocks the other control block 20.

All of the slide members 26 are normally biased into one position, such as that illustrated in FIGURE 3. This bias may be provided by gravity when the shaft 15. is vertical and may beaugmented by a spring (not shown) if desired, which would provide such bias if the shaft 15 were installed horizontally.

By the foregoing structure, means is provided to prevent the simultaneous opening of any second one of the doors 11-13. The means 20, 26 leaves one of the doors 11 13 free to be pivoted, one at a time.

Means are also provided for preventing the pivoting of such one door if the proper coin deposit has not been made. To this end, a drive connection is provided between each of the doors 11-13 and the shaft 15 to effect pivoting of the shaft 15 in response to pivoting of any one of the doors. This preferably comprises a lost motion connection of the pin and slot type as shown in FIG- URE 2. The shaft 15 thus is provided with a pin 33 for each of the hub portions 17, each pin 33 being fixedly secured in the shaft 15, such as by a press fit, and each pin 33 projecting radially through the nylon bearing 18 and into a slot extending from a drive shoulder 34 to an opposite slot end 35. When the door 12 is pivoted toward the open position, the driving shoulder 34 acts on the projecting portion of the pin 33 and causes the shaft to turn in a counterclockwise direction as viewed. If another of the doors were to be so opened, the projecting portion of the pin 33would be permitted to move freely through or relatively to the slot in view of the clearance provided by the end 35 thereof and have no effect on the door 12. Thus pivoting of any one of the doors effects corresponding pivoting of the pivot shaft 15. If desired, the shaft 15 could be connected directly to a coin-responsive acceptor mechanism. Such a connection would in some instances be disadvantageous in that it is not always convenient to have the acceptor mechanism connected and disposed near one end of the pivot shaft 15. More significantly, the mechanical advantage which could be obtained by grasping the knob 14 would render the acceptor subject to damage by one applying too hard a force tending to open the door when no coin deposit has been made.

Therefore, in accordance with a further principle of the present invention, means are provided to render the shaft 15 substantially non-pivotable if the proper coin deposit has not been made.

Referring to FIGURE 5, the shaft 15 is provided with and corotatably supports an arm 36. A lock member 37 is pivoted as at 38 to the arm 36. The lock member 37 is slidable in a plane or space defined by a pair of rigid structural walls or members 39, 40 of the vending machine, being normally biased at a pad 41 against the Wall 41) by a bias means or spring 42 acting therebetween. The spring 42 also biases the lock member 37 in one direction in such plane, which lock member, acting through the arm 36 and the shaft 15,'also acts throughthe drive connection provided by the pin 33 to bias each of the doors 11-13 in a closed position or direction. Upon release of any door, the spring 42 acts through the elements described to close such door.

Also secured to the lock member 37, and pivoted thereto, is a control rod 43, the other end of which is shown broken away. The broken-away end coaets with a conveniently located coin mechanism which allows .the con trol rod 43 to shift axially in response topivoting of the shaft 15 when a proper coin deposit has been made. In the absence of such coin deposit, the coin mechanism arrests axial movement of the control rod "43 .to cause its pivotal connection 44 to serve as a'fulcrum so that further pivoting of the arm 36 acts on the lock member 37 at 38 to rock the lock member 37 about the pivotal connection 44, thereby bringing a detent or locking surface 45 into abutting engagement with an abutment 46 on the stationary element 39. The spring 42 normally holds the lock or detent 45 out of engagement and retracted from the fixed abutment 46, and the detent 45 can move into engagement therewith only when axial movement of the control rod 43 is arrested by the coin mechanism (not shown). The bulk of the force applied to the shaft'15 by attempted opening of the first door will therefore be opposed by the abutment 46, thereby protecting the coin mechanism against excessive forces.

Referring to FIGURE 2, the nylon guide locks 27 are secured in any convenient manner to a rigid support member 47 which is stationary.

By this structure, only one product door may be opened at a time, and such one door is openable only when the proper coin deposit has been made. Attempted opening of any additional door simultaneously with the authorized opening of one door is blocked by the various slide members 26 acting directly on the control blocks 20 of such door. Any attempted opening of a first door in the absence of a proper coin deposit, is not only opposed by the coin mechanism, but such opposition is augmented by or magnified by the lock member 37 which protects the coin mechanism from undue forces.

Although various minor modifications might be suggested by those versed in the art, it should be understood that we wish to embody within the scope of the patent warranted hereon all such embodiments as reasonably and properly come within the scope of our contribution to the art.

We claim as our invention:

1. In a vending machine, the structure comprising in combination:

(a) a plurality of doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

(b) a cam block fixedly secured to one of said doors and pivotable therewith about said axis;

(c) stop means fixedly secured to the other of said doors; and

(d) a slide member engageable with and movable by said cam block, in response to pivoting of said one of said doors from said closed position, into juxtaposition with said stop means and engageable thereby to prevent any simultaneously attempted substantial opening of said other of said doors.

2. In a vending machine, the structure comprising in combination:

(a) a plurality of doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

(b) a cam block fixedly secured to one of said doors and pivotable therewith about said axis;

(c) a slide member engageable with and normally movable by said cam block in response to pivoting of said one of said doors from said closed position; and

(d) stop means fixedly secured to the other of said doors and pivotable therewith about said axis, in response to pivoting of said other of said doors from said closed position, into juxtaposition with said slide member and engageable thereby to prevent any simultaneously attempted substantial opening of said one of said doors.

3. In a vending machine, the structure comprising in combination:

(a) a plurality of doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

(b) a cam block fixedly secured to one of said doors and pivotable therewith about said axis;

(c) stop means fixedly secured to the other of said doors; and

(d) a slide member engageable with and movable by said cam block, in response to pivoting of said one of said doors from said closed position, into juxtaposition with said stop means and engageable thereby to prevent any simultaneously attempted substantial opening of said other of said doors;

(e) said stop means being pivotable about said axis with said other of said doors, in response to pivoting of said other of said doors from said closed position, into juxtaposition with said slide member and engageable thereby to prevent any simultaneously attempted substantial opening of said one of said doors.

4. In a vending machine, the structure comprising in combination:

(a) a series of at least three doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

(b) a pair of cam blocks respectively fixedly secured to a first and a second of said doors and pivotable therewith about said axis;

(c) a pair of stop means respectively fixedly secured to said second and a third of said doors; and

(d) a first and a second slide member respectively normally individually engageable with and movable by said cam blocks, in response to pivoting of one of said first and said second doors from said closed position, into juxtaposition with the corresponding one of said pair of stop means, said first slide member being engageable with said second slide member during said pivoting of said first door to move it also into juxtaposition with said stop means of said third of said doors;

(e) said pair of stop means being respectively pivotable about said axis with said second and said third of said doors, in response to pivoting of one of said second and said third doors from said closed position, into juxtaposition with the corresponding one of said slide members and engageable thereby to prevent respectively any simultaneously attempted substantial opening of said first and said second of said doors, said second slide member being engageable with said .first slide member during said pivoting of said third door also to prevent any simultaneously attempted opening of said first of said doors.

5. In a vending machine, the structure comprising in combination:

(a) a series of at least three doors each pivotally supported for swinging between a normally closed position and an open position;

(b) a series of control blocks respectively secured to each of said doors and pivotable therewith, and normally disposed in a line, at least all but an endmost one of said blocks having a cam surface, and at least all but an opposite endmost one of said blocks having integral stop means; and

(c) a series of aligned slide members each respectively movable by the cam surface of a pivoted one of said blocks and operative to successively engage and move any other of said slide members disposed at one side thereof into blocking juxtaposition with corresponding ones of said stop means, any other of said slide members disposed at the opposite side of said pivoted block being successively engageable with each other and with said stop means of said pivoted one of said blocks.

6. In a vending machine, the structure comprising in combination:

(a) a series of doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

' (b) a series of control blocks respectively fixedly secured to each of said doors and pivotable therewith about said axis; and

(c) a series of slidably supported slide members respectively received between and engageable with adjacent pairs of said control blocks;

(d) each of said control blocks, in response to pivoting of its door, being operative to successively shift any of said slide members at one side thereof into a doorblocking position and to successively block movement of any of said slide members at the other side thereof out of a door-blocking position.

7. In a vending machine, the structure comprising in combination:

(a) a plurality of at least two doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

(b) a like plurality of control blocks respectively fixedly secured to each of said doors and pivotable therewith about said axis; and

(c) a number of slide members which number i one less than said plurality, each slide member being slidably supported between and engageable with a pair of said control blocks for movement between two positions, each slide member in one of said positions blocking pivoting of one of said pair of control blocks, and in the other of said positions blocking the pivoting of the other of said pair of control blocks.

8. In a vending machine, the structure comprising in combination:

(a) a plurality of at least two doors each pivotally supported for swinging about an axis between a normally closed position and an open position;

(b) a like plurality of control blocks respectively fixedly secured to each of said doors and pivotable therewith about said axis; and

(c) a number of slide members which number is one less than said plurality, each slide member being slidably supported between and engageable with a pair of said control blocks for movement between two positions, each slide member in one of said positions blocking pivoting of one of said pair of control blocks, and in the other of said positions blocking the pivoting of the other of said pair of control blocks;

(d) each of said control blocks being operative, as its door is pivoted to an open position, to shift any of said slide members at one side thereof to a first of said slide-member positions and to hold any of said slide members at the other side thereof in a second of said slide-member positions.

9. In a vending machine, the structure comprising in combination:

(a) a plurality of at least two doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

(b) a like plurality of control blocks respectively fixedly secured to each of said doors and pivotable therewith about said axis; and

(c) a number of slide members which number i one less than said plurality, each slide member being slidably supported between and engageable with a pair of said control blocks for movement between two positions, said slide members being normally biased into one of said positions, each slide member in said one of said positions blocking pivoting of said one of said pair of control blocks, each slide member when moved to the other of said positions blocking the pivoting of the other of said pair of control blocks.

10. In a vending machine, the structure comprising in combination:

(a) a plurality of at least two doors each pivotally supported for swinging about an axis, between a normally closed position and an open position;

(b) alike plurality of control blocks respectively fixedly secured to each of said doors and pivotable therewith about said axis; and

(c) a number of slide members which number is one less than said plurality, each slide member being slidably supported between and engageable with a pair of said control blocks for movement between two positions, said slide members being normally biased into one of said positions, each slide member Q w in said one of said positions blocking pivoting of said one of said pair'of control blocks, each slide member when moved to the other of said positions blocking the pivoting of the other of said pair of control blocks;

(d) each of said control blocks being operative, as its door is pivoted to an open position, to shift any of said slide members at one side thereof to a first of said slide-member positions and to hold any of said slide members at the other side thereof in a second of said slide-member positions.

11. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

(c) a drive connection between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position;

(d) means secured to said shaft and operative to prevent said pivoting thereof in the absence of a proper.

coin deposit; and

(e) means operative in response to said swinging of said one door to prevent simultaneous opening of any other one of said doors.

12. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

(c) a drive connection between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position;

((1) means secured to said shaft and operative to prevent said pivoting thereof in the absence of a proper coin deposit;

(e) a like plurality of control blocks respectively secured to each of said doors and pivotable therewith; and

(f) a number of slide members which number is one less than said plurality, each slide member being slidably supported between a pair of said control blocks for movement between two positions, each slide member in one of said positions blocking pivoting of one of said pair of control blocks, and in the other of said positions blocking the pivoting of the other of said pair of control blocks to prevent simultaneous opening of any other one of said doors.

13. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

(c) a drive connection between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position;

((1) means operative through said shaft and said drive connections for normally yieldably biasing said doors into said closed position; and

(e) means operative in response to said swinging of said one door to prevent simultaneous opening of any other one of said doors.

14. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

(0) a drive connection between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position;

(d) means secured to said shaft and operative to prevent said pivoting thereof in the absence of a proper coin deposit, said means being yieldably biased and operative through said shaft and said drive connections for normally yieldably biasing said doors into said closed position; and

(e) means operative in response to said swinging of said one door to prevent simultaneous opening of any other one of said doors.

15. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

() a drive connection between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position;

(d) means secured to said shaft and operative to pivot said shaft in an opposite direction in response to release of said one of said doors; and

'(e) means operative in response to said swinging of said one door to prevent simultaneous opening of any other one of said doors. i

16. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

(0) a lost motion connection of the pin and slot type between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position; v

(d) means secured to said shaft and operative to pre vent said pivoting thereof in the absence of a proper coin deposit; and 1 (e) means operative in response to said swinging of said one door to prevent simultaneous opening of any other one of said doors.

17. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

(0) a drive connection between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position;

(d) an arm corotatably secured to said shaft;

(e) a lock member pivoted on said arm;

(f) a control rod pivoted on said lock member and being yieldably movable lengthwise in the presence of a proper coin deposit;

(g) a fixed abutment against which said lock member is pivoted by said arm with said control rod acting as a fulcrum in the absence of a proper coin deposit for arresting said pivoting of said shaft; and

(h) means operative in response to said swinging of said one door to prevent simultaneous opening of any other one of said doors.

18. In a vending machine, the structure comprising in combination:

(a) a shaft supported for pivoting about its axis;

(b) a plurality of at least two doors each supported on said shaft for swinging between a normally closed position and an open position;

(c) a drive connection between each of said doors and said shaft by which said shaft is pivoted in response to swinging of any one of said doors to its open position;

(d) an arm corotatably secured to said shaft;

(e) a lock member supported to slide in a plane in response to pivoting of said arm in the presence of a proper coin deposit;

(f) a fixed abutment adjacent to said plane and against which said lock member is pivoted by said arm in the absence of a proper coin deposit;

(g) a spring urging said lock member away from said abutment and into said plane; and

(h) means operative in response to said swinging of said one door to prevent simultaneous opening of any other one of said doors.

19. In a vending machine, the structure comprising in combination:

(a) a plurality of at least two doors each pivotally supported for swinging between a normally closed position and an open position;

(b) a like plurality of control blocks respectively secured to each of said doors and pivotable therewith; and

(c) a number of slide members which number is one less than said plurality, each slide member being slidably supported between a pair of said control blocks for movement between two positions, each of said slide members having a notch receptive of one of said control blocks in one of said positions to prevent pivoting thereof, and each of said slide members in the other of said positions being engageable simultaneously with said one of said blocks when it is pivoted and with the other of said blocks to prevent pivoting thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,975,922 3/59 Hsu et a1. 221- LOUIS I DEMBO, Primary Examiner.

HADD S. LANE, Examiner. 

1. IN A VENDING MACHINE, THE STRUCTURE COMPRISING IN COMBINATION: (A) A PLURALITY OF DOORS EACH PIVOTALLY SUPPORTED FOR SWINGING ABOUT AN AXIS, BETWEEN A NORMALLY CLOSED POSITION AND AN OPEN POSITION; (B) A CAM BLOCK FIXEDLY SECURED TO ONE OF SAID DOORS AND PIVOTABLE THEREWITH ABOUT SAID AXIS; (C) STOP MEANS FIXEDLY SECURED TO THE OTHER OF SAID DOORS; AND (D) A SLIDE MEMBER ENGAGEABLE WITH AND MOVABLE BY SAID CAM BLOCK, IN RESPONSE TO PIVOTING OF SAID ONE OF SAID DOORS FROM SAID CLOSED POSITION, INTO JUXTAPOSITION WITH SAID STOP MEANS AND ENGAGEABLE THEREBY TO PREVENT ANY SIMULTANEOUSLY ATTEMPTED SUBSTANTIAL OPENING OF SAID OTHER OF SAID DOORS. 